The present invention relates to a computer system and a method of controlling the bootstrap and, more particularly, to a computer system capable of using a removable disk drive such as a CD-ROM drive as a boot device, and a method of controlling the bootstrap.
In a personal computer, a floppy disk drive or a hard disk drive has conventionally been used as a boot device for bootstrapping the operating system.
Recently, specifications for performing a bootstrap from a CD-ROM drive are determined, and corresponding CD-ROM media are being commercially available. These specifications use a CD-ROM medium on which an operating system and CD-ROM driver software are recorded. The use of this CD-ROM medium enables bootstrapping the operation system from the CD-ROM drive in powering up the personal computer, similarly to a boot from an FDD or an HDD.
Most of CD-ROM drives incorporated in personal computer main bodies are IDE drives, which receive power from the personal computer main bodies. A CD-ROM drive of this type employs a tray scheme excellent for a small size and an easy medium exchange operation. The CD-ROM drive of the tray scheme has an EJECT button for drawing out the tray, and a recent tray is of an electromagnetic locking scheme. If the computer main body is not powered up, the tray cannot be drawn out even upon depressing the EJECT button.
Since the tray is not opened even upon depressing the EJECT button while the personal computer is OFF, a CD-ROM medium cannot be loaded in the CD-ROM drive with the personal computer being OFF. Even if the bootstrap is desired to be executed from the CD-ROM medium, the boot CD-ROM medium cannot be inserted. When the personal computer is powered up in this state, even if the boot is set to be preferentially performed from the CD-ROM, the bootstrap is undesirably executed from the FDD or the HDD having a next boot priority because no CD-ROM medium is loaded.